Nitrogen-Doped Porous Carbons Derived from Polypyrrole-Based

Subscriber access provided by READING UNIV

Article

Nitrogen-Doped Porous Carbons Derived from PolypyrroleBased Aerogels for Gas Uptake and Supercapacitors Yanan Sun, Zhu-Yin Sui, Xin Li, Pei-Wen Xiao, Zhixiang Wei, and Bao-Hang Han ACS Appl. Nano Mater., Just Accepted Manuscript • DOI: 10.1021/acsanm.7b00089 • Publication Date (Web): 03 Jan 2018 Downloaded from http://pubs.acs.org on January 5, 2018

Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a free service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are accessible to all readers and citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.

ACS Applied Nano Materials is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.

Page 1 of 34 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

ACS Applied Nano Materials

Nitrogen-Doped Porous Carbons Derived from Polypyrrole-Based Aerogels for Gas Uptake and Supercapacitors Ya-Nan Sun,†,‡ Zhu-Yin Sui,† Xin Li,† Pei-Wen Xiao,† Zhi-Xiang Wei,*,†,‡ and Bao-Hang Han*,†,‡

† CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, China ‡ University of Chinese Academy of Sciences, Beijing 100049, China

ACS Paragon Plus Environment

ACS Applied Nano Materials 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 2 of 34

ABSTRACT: A novel polypyrrole-based aerogel (PPA) with three-dimensional structure is synthesized through a simple hydrothermal process of the homogeneous dispersion consisting of pyrrole and block copolymer, followed by freeze-drying. The block copolymer plays a role of dispersant, which can be ascribed to the hydrophilic–hydrophobic interaction between pyrrole-based units and block copolymer. Compared with conventional bulk polypyrrole powder, the PPA exhibits higher porous attributes, which provide favorable conditions to the subsequent activation procedure. A nitrogen-doped porous carbon (NPC) with high porosity is then prepared after a physical activation treatment of PPA using carbon dioxide as an activation agent. The structure and porous property of NPC are characterized by scanning electron microscopy, transmission electron microscopy, infrared spectroscopy, X-ray photoelectron spectroscopy, and nitrogen adsorption– desorption experiments. The as-made NPC-950-100 possesses a large Brunauer–Emmett– Teller specific surface area (2330 m2 g–1), large pore volume (2.54 cm3 g–1), and nitrogen doping (4.1 wt%). These properties result in a high carbon dioxide uptake capacity of 20.5 wt% at 273 K and 1.0 bar. Furthermore, NPC-950-60 also displays a decent specific capacitance (156 F g–1 at 0.1 A g–1) and an excellent long-term cycling stability (~100 % capacitance retention at 5 A g–1 after 10000 cycles).

KEYWORDS: Polypyrrole; Aerogel; Porous Carbon; Adsorption; Supercapacitor

2 ACS Paragon Plus Environment

Page 3 of 34 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


INTRODUCTION Porous carbon materials with the potential applications in gas adsorption and energy storage have aroused widespread concern owing to their large specific surface area, excellent electrical conductivity, and high stability. 1,2,3,4 To date, porous carbons are usually prepared through activation treatments that can be classified into chemical activation and physical activation. 5 Chemical activation refers to a method of using chemical reagent, such as KOH, NaOH, or H3PO4, as an activation agent to prepare the porous carbon.6,7 Meanwhile, physical activation refers to a method of producing porous carbon using an oxidizing gas, such as carbon dioxide or water vapor, as an activation agent.

8

Comparing with chemical activation, physical activation is much more

environmentally friendly because of the advantage of low cost, no additional washing procedure, and no corrosion during the activation treatment. 9 Park and co-workers prepared a microporous carbon through physical activation of poly (vinylidene fluoride) using a carbon dioxide gas as activation agent. They reported the effect of activation temperature on the structural properties and the electrochemical performance influenced by surface functionalities of the activated microporous carbons.10 Jaroniec and co-workers described the synthesis of porous carbons derived from phenolic resin by means of the softand hard- templating method, followed by physical activation with water vapor and carbon dioxide.11 Our group reported a kind of three-dimensional (3D) porous carbon prepared by a physical activation of graphene aerogel using steam as activation agent. The activated



Page 4 of 34

aerogel possessed a high Brunauer–Emmett–Teller (BET) specific surface area and a large pore volume with a 3D network structure.12 Nevertheless, physical activation is much more moderate than chemical activation. The weak activation strength of the physical activation always limits its applications in many kinds of nonporous materials. Therefore, aerogel with 3D network structure can provide an approach to take full advantage of the physical activation. Since silica aerogel was first reported by Kistler in 1931,13 several other kinds of aerogel materials with 3D structure have been prepared such as carbon nanotube aerogel,14 graphene aerogel,

15 , 16

polypyrrole-based aerogel (PPA),

17

and other carbon

aerogels. 18,19,20,21 Considering the high cost of carbon nanotube aerogel or graphene aerogel, PPA might be a proper material to prepare the nitrogen-doped porous carbon (NPC) through a physical activation method. Up to now, there are several kinds of molecules or polymers, such as phytic acid,17 agarose,22 chitosan,23 and poly (acrylic acid),24 have been used to prepare PPA. However, it is still necessary to develop a novel approach to prepare PPA on a large scale. To date, work on the preparation of PPA by using block copolymer as a dispersant has never reported. Block copolymer with hydrophobic and hydrophilic blocks can facilitate the homogeneous dispersion of the insoluble pyrrole-based materials due to the hydrophilic–hydrophobic interaction between pyrrole-based units and the block copolymer, thus making it easy to synthesize the PPA in bulk. Here, we report a facile method to prepare a novel PPA with 3D structure by using


Page 5 of 34 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


block copolymer as a dispersant. Comparing with the conventional polypyrrole powder, PPA possesses higher porous properties, which can provide the accessible pore structure to make the physical activation sufficient. After the subsequent carbon dioxide activation treatment, NPC with large BET specific surface area (2330 m2 g–1) and nitrogen content (4.1 wt%) was obtained. The excellent porosity and high surface area of NPC can be ascribed to the physical activation of PPA with 3D structure. According to these features, the carbon dioxide adsorption capacity of NPC-950-100 can be as high as 20.5 wt% at 1.0 bar and 273 K. Moreover, the high porosity and chemical doping also provide the NPC-950-60 materials with specific capacitance of 156 F g–1 at 0.1 A g–1 and excellent long-term cycling stability (~100 % capacitance retention at 5 A g–1 after 10000 cycles).

EXPERIMENTAL SECTION Materials Poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (PEG-PPG-PEG, Pluronic® P-123, Ma =5800) was purchased from Sigma-Aldrich (Shanghai) Trading Co., Ltd. Pyrrole was provided from Aladdin Industrial Corporation, Shanghai, China. Hydrochloric acid (37 wt%), sulphuric acid (98 wt%), and ammonium persulfate (98 wt%) are of analytically pure and were obtained from Beijing Chemical Reagents Company, China. Polytetrafluoretyhylene (PTFE, 60 wt% dispersion in water) and carbon black (99.9 %) were bought from Sigma-Aldrich (Shanghai) Trading Co., Ltd.



Page 6 of 34

All chemicals were used without further purification. Ultrapure water (18 MΩ cm) was produced through a Millipore-ELIX water purification system. Carbon dioxide (99.5 % purity) and nitrogen (99.999 % purity) were purchased from Beijing Haike Yuanchang Gas Co. Ltd., China. Preparation of PPA P123 (2.0 g) was dissolved in aqueous hydrochloric acid solution (2.0 M, 60 mL) at 35 °C in 1 h, followed by the addition of pyrrole monomer (1 mL). The solution was stirred for 30 min until it became clear. Then, aqueous ammonium persulfate solution (1.2 M, 15 mL) was added dropwise into the clear solution. After being stirred for 10 min, the mixture was treated through a hydrothermal process using a Teflon-lined stainless-steel autoclave at 180 °C for 12 h. Then the hydrogel was prepared after the autoclave was cooled to room temperature. For the typical procedure, PPA was finally obtained via a freeze-drying process of the as-prepared hydrogel. As a control sample, polypyrrole powder was prepared without the addition of P123. Pyrrole monomer (1 mL) was dissolved in aqueous hydrochloric acid solution (2.0 M, 60 mL) at 35 °C in 1 h. To the pyrrole solution, aqueous ammonium persulfate solution (1.2 M, 15 mL) was added dropwise. The mixture was stirred for 10 min, and the black precipitate appeared. The polypyrrole powder was obtained after the filtration and drying process. Preparation of NPC NPC was prepared by carbon dioxide activation of PPA. PPA was activated by heat


Page 7 of 34 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


treatment under carbon dioxide atmosphere up to a temperature ranging from 850 to 950 °C (activation time: 30–100 min). In a typical procedure, PPA was put into a tube furnace and heated to the activation temperature by a heating rate of 10 °C min–1 under nitrogen atmosphere. When the temperature was achieved to the activation temperature (850, 900, or 950 °C), the atmosphere in the furnace was changed into carbon dioxide and kept throughout the activation process (30, 60, or 100 min). After the activation process, the atmosphere in the furnace was changed back to the nitrogen. After cooling down to room temperature, NPC was finally obtained. A series of samples were prepared to study the influence of temperature or time in the activation procedure. These samples were denoted as NPC-T-t (“t” represents activation time and “T” represents activation temperature). When the activation temperature was changed to 850, 900, or 950 °C with the activation time of 100 min, the corresponding samples were defined as NPC-850-100, NPC-900-100, and NPC-950-100. The other samples are named accordingly. As a control sample, polypyrrole powder was additionally treated in the furnace under the same activation condition. Meanwhile, PPA was also heated at the same temperature under the nitrogen atmosphere, which was denoted as carbonized polypyrrole-based aerogel (cPPA). Instrumental Characterization Transmission electron microscopy (TEM) images and scanning electron microscopy (SEM) images were observed from a Tecnai G2 20 S-TWIN microscope (FEI, U.S.A.) and



Page 8 of 34

an S-4800 field emission scanning electron microscope (Hitachi Ltd., Japan), respectively. Infrared (IR) spectra were obtained on Fourier transform infrared (FTIR) spectroscopy instrument (PerkinElmer, U.S.A.). X-ray diffraction (XRD) patterns were conducted through a D/MAX-TTRIII(CBO) X-ray diffraction instrument (Rigaku Co., Japan) using Cu Kα radiation. Raman spectra were carried out on an inVia Raman spectrometer (Renishaw plc, U.K.). The wavelength of the laser during the Raman spectra measurement was 514 nm. Thermal gravimetric analysis (TGA) was measured by a Pyris Diamond thermogravimetric/differential thermal analyzer (PerkinElmer, U.S.A.) in nitrogen atmosphere (heating rate: 10 °C min–1). Chemical elemental analysis was conducted on a Flash EA 1112 (Thermo Electron SPA, U.S.A.) to obtain the content of carbon, hydrogen, and nitrogen in the samples. X-ray photoelectron spectroscopy (XPS) was measured using Al Kα radiation at 300 W, which was carried out on an ESCALab220i-XL electron spectrometer (VG Scientific Ltd., U.K.). The adsorption–desorption isotherms of nitrogen and carbon dioxide were measured at 77 and 273 K by 3-Flex and TriStar II 3020 surface area and porosity analyzer (Micromeritics Instrument Corporation, U.S.A.). The pore parameters were obtained through the nitrogen adsorption–desorption isotherms. The degas temperature and time of all the porous materials were 120 °C and 12 h, respectively. Electrochemical experiments were carried out by an EG&G Princeton Applied Research VMP3 workstation (Bio-Logic Science Instruments, France). Electrodes were


Page 9 of 34 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


prepared by mixing 10 wt% conducting carbon black, 5 wt% PTFE, and 85 wt% active material. Two-electrode cell systems with the current collector of gold grid were employed throughout all the electrochemical measurements. There were two working electrodes assembled in the supercapacitor using aqueous sulfuric acid solution (1.0 mol L–1) as the electrolyte, which were separated by a hydrophilic membrane. The galvanostatic charge– discharge cycling, cyclic voltammetry (CV) tests, and capacitance stability measurement were used to analyze the electrochemical performances of the obtained electrodes. The potential range of the galvanostatic charge–discharge cycling and CV measurements was 0–1.0 V.

RESULTS AND DISCUSSION



Page 10 of 34

Figure 1. Schematic illustration of the synthesis of nitrogen-doped porous carbon (NPC).

Comparing with conventional bulk polypyrrole powder, PPA with 3D structure is much more beneficial for the physical activation using carbon dioxide as activation agent. As measured in Figure S1, polypyrrole powder exhibits much lower BET surface area (20 m2 g–1) than PPA (120 m2 g–1). The high porosity of PPA provides the accessible pore structure to allow the carbon dioxide molecule to enter the PPA material easily, which can make the subsequent physical activation sufficient. Therefore, the strategy to produce the porous materials based on polypyrrole is to form 3D porous PPA, followed by a carbon dioxide activation of PPA to prepare NPC. As shown in Figure 1, pyrrole monomer and P123 were dissolved in aqueous hydrochloric acid solution with the subsequent addition of ammonium persulfate. In this procedure, P123 plays a role of dispersant that can avoid the conglomeration of pyrrole-based units,25,26 which can be ascribed to the hydrophilic– hydrophobic interaction between pyrrole-based units and P123. When P123 is dissolved in the aqueous hydrochloric acid solution, the hydrophobic pyrrole-based units will locate themselves at the hydrophobic blocks of P123, while the hydrophilic blocks of P123 are easy to dissolve in the water. PPA was then obtained through a hydrothermal process and a freeze-drying process. The photograph of PPA is shown in Figure S2 (Supporting Information). After an activation treatment of PPA using carbon dioxide as an activation agent, the black powder of NPC can be obtained eventually. The process during the


Page 11 of 34 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


activation treatment can be expressed by the reaction: C + CO2 = 2CO.27 In this procedure, carbon dioxide first removes the non-organized carbon intermediate formed during the carbonization and then reacts with graphitic carbon in the material.8

Figure 2. SEM images of polypyrrole-based aerogel (PPA) (a) and nitrogen-doped porous carbon (NPC-950-100) (b). TEM images of PPA (c) and NPC-950-100 (d). (e) Energy dispersive spectrometer (EDS) element mapping of nitrogen and carbon of NPC-950-100. SEM and TEM were employed to investigate the morphology and structure of the PPA and NPC. The SEM images of PPA (Figure 2a) and NPC-950-100 (Figure 2b) clearly show the polypyrrole spheres with the size of ~50 nm in PPA and NPC-950-100, and the



Page 12 of 34

aggregation of these spheres forms a macroporous assembly. Apparently, the spherical morphology of PPA was not destroyed during carbon dioxide activation. The TEM images (Figure 2c and Figure 2d) reveal the structure of PPA and NPC-950-100. It can be clearly observed that the interconnected porous structure was exhibited in both PPA and NPC-950-100. In addition, the SEM and TEM images of cPPA are also displayed in Figure S3 (Supporting Information). Furthermore, the energy dispersive spectrometer (EDS) element mapping of NPC-950-100 is displayed in Figure 2e. It is obvious that nitrogen element is homogeneously distributed in NPC-950-100. It is necessary to analyze the nitrogen species to study their influence on gas sorption and electrochemical performance. The chemical composition was characterized by XPS. All the PPA, cPPA, and NPC-950-100 samples show the existence of C 1s, N 1s, and O 1s in Figure 3a. However, there is an obvious decrease in the intensity of N 1s and O 1s after activation treatment. This phenomenon can be ascribed to the reaction between carbon and oxygen and the removal of nitrogen during the activation procedure at high temperature.3 The analysis of trace chemical elements shows that the nitrogen content of PPA is 7.5 wt% and the nitrogen content of NPC-950-100 is 4.1 wt%. The N 1s spectrum (Figure 3b) displays different types of nitrogen in all the three samples. As expected, three types of nitrogen in PPA, cPPA, and NPC-950-100 can be distinguished as pyrrolic nitrogen (399.9 eV), pyridinic nitrogen (398.7 eV), and quaternary-N (400.9 eV).28,29,30 When the PPA was converted into cPPA and NPC-950-100 under high temperature through carbonization and


Page 13 of 34 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


activation, respectively, the content of quaternary-N increase distinctly and there is little pyrrolic nitrogen. This result indicates the transformation from pyrrolic nitrogen to quaternary-N and pyridinic nitrogen in the carbonization or activation process. 31 , 32 Therefore, the heat treatment procedure is beneficial to introduce some surface functional sites into the porous carbon materials.3 Furthermore, the plentiful nitrogen species can provide chemically active sites to improve the uptake of carbon dioxide and the power density of supercapacitors.33 The XPS C 1s spectra of NPC-950-100 shown in Figure S4 (Supporting Information) reveals four peaks centered at 284.8 eV (C–C), 285.9 eV (C–N), 286.8 eV (C–O), and 287.9 eV (C=O),16,34 suggesting the existence of nitrogen and oxygen. Figure S5 (Supporting Information) shows the TGA curves. It is obvious that NPC-950-100 is more thermally stable than PPA and cPPA. There is still ~92 % mass retention in NPC even when it is heated to 800 °C. The IR spectra of PPA, cPPA, and NPC-950-100 are shown in Figure 3c. It is clear that PPA possesses the characteristic peaks of polypyrrole, such as the N–H and/or O–H stretching vibrations (3000–3700 cm–1), C–H stretching vibrations (3000 and 2850 cm–1), C=O stretching vibrations (1700 cm–1), C=C ring-stretching vibrations (1590 and 1476 cm– 1

), C–N stretching vibrations (1355 cm–1), in-plane C–H and N-H deformation (1060–1630

cm–1), and out-of-plane C–H and N–H deformation (800–970 cm–1).35,36,37,38 Nevertheless, the characteristic peaks of polypyrrole disappear in cPPA and NPC-950-100 appearantly.37,38 The wide-angle powder XRD patterns of the three samples are displayed in



Figure 3d. A broad and weak peak centered at around 2θ = 24 ° (d002) is observed in all the three samples, indicating the graphitization of the polypyrrole during the hydrothermal reduction and heat a

C 1s

N 1S NPC-950-100

PPA

N 1s

Intensity / a.u.

Intensity / a.u.

b

O 1s

cPPA

cPPA

NPC-950-100

1200

1000

PPA

800

600

400

200

0

394

396

Binding Energy / eV

c

398

400

402

404

406

408

Binding Energy / eV

d

cPPA

Intensity / a.u.

NPC-950-100

Intensity / a.u.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 14 of 34

NPC-950-100

cPPA

PPA

PPA 4000

3000

2000

1000

10

-1

Wavenumber / cm

20

30

40

50

60

2 Theta / degree

Figure 3. XPS survey spectra (a), N 1s spectra (b), IR spectra (c), and XRD patterns (d) of polypyrrole-based aerogel (PPA), carbonized polypyrrole-based aerogel (cPPA), and nitrogen-doped porous carbon (NPC-950-100). treatment procedure. There is also a weak peak centered at around 2θ = 44 ° (d100) in cPPA and NPC-950-100, confirming the increase in graphitization extents with the increasing


Page 15 of 34 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


temperature. 39 As shown in Figure S6 (Supporting Information), the cPPA and NPC-950-100 were also measured by Raman spectra. There are two common characteristic peaks, D-band (1350 cm–1) and G-band (1590 cm–1), existing in the two samples. D- and G-bands reveal the presence of carbon atoms from the defect structure and the aromatic structure, respectively, suggesting the existence of the graphitic carbon in the two samples.40 The porous properties of NPC were characterized by nitrogen adsorption–desorption isotherm measurements. Figure 4a shows the nitrogen adsorption–desorption isotherm of NPC-950-100, which possesses type I and type II isotherms.41 There is a rapid increase in the low relative pressure range (P/P0=0~0.10) and a decent increase in the high relative pressure range (P/P0=0.80~1.00) in NPC-950-100, which indicate that NPC-950-100 has a large number of micropores and some macropores. In comparison, the nitrogen adsorption– desorption isotherms of PPA and cPPA are also displayed in Figure 4a. The isotherms of PPA and cPPA show almost no increase in the low relative pressure range, suggesting that NPC-950-100 possesses more micropores than PPA and cPPA owing to the activation treatment. NPC-950-100 reveals a high BET specific surface area of 2330 m2 g–1, which is much higher than cPPA (170 m2 g–1) and PPA (120 m2 g–1). As mentioned before, the porosity of polypyrrole powder (Figure S1, Supporting Information) was also measured. The BET specific surface area of polypyrrole powder is only 20 m2 g–1, which is much lower than that of PPA, confirming the increase in the porosity of the aerogel with 3D



structure. Furthermore, the nitrogen adsorption–desorption isotherm of the carbon dioxide activated polypyrrole powder is displayed in Figure S7 (Supporting Information). The low BET specific surface area (520 m2 g–1), comparing with the NPC, also reveals the vital

3

Adsorbed Volume, STP / cm g

-1

effect of the 3D structure in the PPA during the activation treatment.

2000

a

1500 NPC-950-100

1000

500 cPPA

0

PPA

0.0

0.2

0.4

0.6

0.8

1.0

-1

Pore Volume, dV /dD / cm g nm

-1

Relative Pressure (P/P0)

1.0

b

3

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 16 of 34

1.30

0.8 1.69

0.6 NPC-950-100

0.4

0.69 2.31

0.2 cPPA

0.0

PPA

1

10

100

Pore Size / nm

Figure 4. (a) Typical nitrogen adsorption–desorption isotherms and (b) non-local density


Page 17 of 34 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


functional theory (NLDFT) pore size distribution profiles of polypyrrole-based aerogel (PPA), carbonized polypyrrole-based aerogel (cPPA), and nitrogen-doped porous carbon (NPC-950-100). (Open symbols for desorption and solid symbols for adsorption.) Figure 4b shows the pore size distribution analysis based on the non-local density functional theory (NLDFT) method. It can be seen that NPC-950-100 shows four main peaks located at 0.69, 1.30, 1.69, and 2.31 nm, indicating micropores and mesopores are produced during the activation procedure. Hence, according to the analysis of adsorption– desorption isotherm and pore size distribution, there are micropores, mesopores, and macropores in NPC-950-100. It can be concluded that NPC-950-100 possesses the hierarchically porous structure. Meanwhile, the PPA and cPPA are less porous. Table S1 (Supporting Information) summarizes the porosities of the PPA, cPPA, and NPCs obtained from nitrogen adsorption–desorption experiments. It can be found that with the increase in the activation time from 30 to 60 to 100 min at 950 °C, the BET specific surface area of NPC changes from 910 to 1390 to 2330 m2 g–1. The total pore volumes of these NPCs at P/P0 = 0.97 are 0.65, 0.90, and 2.54 cm3 g–1, respectively. Meanwhile, when the activation temperature alters from 850 to 900 to 950 °C with an activation time of 100 min, the BET specific surface area of NPC can also transform from 570 to 940 to 2330 m2 g–1. The total pore volumes of them at P/P0 = 0.97 are 0.73, 0.89, and 2.54 cm3 g–1, respectively. Therefore, it can be concluded that the change in activation time or activation temperature can tune the BET specific surface area and porosity of NPC. As the activation time or



activation temperature increases, the NPC show larger specific surface area and total pore volumes.

20.0

CO2 Adsorbed / wt%

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 18 of 34

NPC-950-100

15.0

10.0

cPPA

5.0

PPA

0.0

0

100 200 300 400 500 600 700 800

Absolute Pressure / mmHg Figure 5. Carbon dioxide adsorption–desorption isotherms at 273 K of polypyrrole-based aerogel (PPA), carbonized polypyrrole-based aerogel (cPPA), and nitrogen-doped porous carbon (NPC-950-100). (Open symbols for desorption and solid symbols for adsorption.) As the large surface area and high nitrogen content are important parameters to improve the adsorption of acidic gas, NPC can be a potential material as an adsorbent for carbon dioxide. Figure 5 displays the carbon dioxide adsorption–desorption isotherms of PPA, cPPA, and NPC-950-100 tested at 273 K. NPC possesses a high uptake capacity of 20.5 wt% for carbon dioxide at 1.0 bar and 273 K, which is higher than many other kinds of porous materials at the same condition.42,43,44 Table S2 (Supporting Information) lists the comparison of carbon dioxide uptake (273 K and 1.0 bar) for different porous adsorbents in


Page 19 of 34 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


previous researches. It can be seen that the carbon dioxide uptake of NPC-950-100 is good compared to those for the listed porous materials. Meanwhile PPA and cPPA show moderate uptake capacities of 3.1 wt% and 8.3 wt% for carbon dioxide under the same condition, respectively. The excellent carbon dioxide adsorption capacity can be ascribed to the presence of element nitrogen, the large BET specific surface area, and the microporosity in NPC-950-100. The main mechanism of the carbon dioxide adsorption in porous carbons is a volume-ﬁlling mechanism and the pore size limits for volume-ﬁlling are in the microporous area. 45 , 46 Furthermore, the almost reversible carbon dioxide adsorption–desorption isotherm of NPC-950-100 indicates that the uptake of carbon dioxide is mainly via physical adsorption or weak interaction. NPC possesses a high surface area, hierarchically porous structure, and decent nitrogen content, which can provide accessible pore structure and plentiful electrochemical active sites. According to these features, NPC may be a potential material used as the supercapacitor electrode. Therefore, in order to evaluate the potentially practical application of NPC, the electrochemical performance of NPC as supercapacitor electrode was tested by using a two-electrode cell system. Figure 6a shows the CV curves of NPC-950-60 examined under different scan rates (2–100 mV s–1). It is quite clear that all of the curves show a square shape, which can imply the nearly ideal electrical-double-layer capacitive characteristic of NPC-950-60. Especially, the CV curve of NPC still remains a quasi-rectangular shape under a high scan rate of 100 mV s–1, which can illustrate a quick



Page 20 of 34

charge propagation capacity of NPC. Despite the nitrogen atoms are existed in NPC-950-60, the redox peaks are unobvious in the two-electrode system, which is consistent with the previous reports.3, 47 , 48 The CV curves of NPC-950-30, NPC-950-100, NPC-900-100, NPC-850-30, activated polypyrrole powder, and cPPA examined under different scan rates (2–100 mV s–1) are also provided in Figure S8 (Supporting Information). The similar quasi-rectangular shape of NPCs can be observed in the CV curves. Meanwhile, the lower area enclosed by the CV curve of cPPA indicates the poor electrochemical performance of cPPA compared with NPCs.49 Galvanostatic charge–discharge curves displayed in Figure 6b were investigated to explore the rate performance of NPC-950-60 under different current densities (0.1–5 A g–1). The voltage–time curves of NPC are close to a linear shape, implying the outstanding electrical performance. The specific capacitance of NPC-950-60 electrode calculated from the slope of the discharge curve was about 156 F g–1 at 0.1 A g–1, which is higher than some other activated porous carbon materials.49,50,51 Meanwhile, as shown in Figure 6c, there is still 135 F g–1 of specific capacitance after the current density increases 50 fold (5 A g–1), which is equivalent to 87 % capacitance retention, indicating its good rate capability. Additionally, the galvanostatic charge–discharge curves of NPC-950-30, NPC-950-100, NPC-900-100, NPC-850-30, activated polypyrrole powder, and cPPA at different current densities (0.1–5 A g–1) are displayed in Figure S9 (Supporting Information). The rate performance of NPCs is much better than those of the activated polypyrrole powder and cPPA. The specific capacitance calculated from the galvanostatic


Page 21 of 34

charge–discharge curves are shown in Figure S10 (Supporting Information). The specific capacitance of NPCs (142–156 F g–1) is much higher than those of the activated polypyrrole powder (80 F g–1) and cPPA (13 F g–1) at 0.1 A g–1, which can be ascribed to the high porosity of the NPCs. 1.2

24

a

b

NPC-950-60

16

NPC-950-60

1.0

8

0.1 A/g 0.5 A/g 1 A/g 3 A/g 5 A/g

0.8

E/V

I / mA

0 -8

-24 -32 0.0

0.2

0.4

0.6

0.8

0.6

0.4

2 mV/s 5 mV/s 10 mV/s 20 mV/s 50 mV/s 100 mV/s

-16

0.2

0.0

0

1.0

200

400

800

1000 1200 1400 1600 1800

140

200

c NPC-950-60

150

100

50

0

600

Time / s

Capacitance Retention / %

-1

E/V

Specific Capacitance / F g

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


0

1

2

3

4

5

d

NPC-950-60

120 100 80 60 40 20 0

0

1000 2000 3000 4000 5000 6000 7000 8000 9000 10000

-1

Current Density / A g

Cycle Number

Figure 6. (a) Cyclic voltammetry (CV) curves of nitrogen-doped porous carbon (NPC-950-60) in sulfuric acid electrolyte (1.0 mol L–1) at different scan rates. (b) Galvanostatic charge–discharge curves of NPC-950-60 at different current densities. (c) The specific capacitance of discharge current density for NPC-950-60. (d) Cycle stability of NPC-950-60 at a current density of 5 A g–1 for 10000 cycles.



Page 22 of 34

Furthermore, as an important parameter, the cyclic life of NPC also need to be investigated to evaluate the charge–discharge stability of the electrode material. As shown in Figure 6d, the cycle stability of NPC-950-60, which was measured by galvanostatic charge–discharge cycling experiments at a current density of 5 A g–1, is excellent and there is mainly no attenuation after 10000 cycles. Table S3 (Supporting Information) shows the comparison of specific capacitance and capacitance retention for different porous carbon electrodes in previous literature. It can be seen that the specific capacitance of NPC-950-60 is in a decent level and the cycle stability of NPC-950-60 is excellent as compared to the reported data. The Nyquist plot of NPC is shown in Figure S11 (Supporting Information). The small diameter of the semicircle in the high-frequency indicates the low charge-transfer resistance.3,52 Meanwhile, the much higher slope of NPCs at the low-frequency region shows that the pore accessibility of NPCs is better than those of activated polypyrrole powder and cPPA. This characteristic can be ascribed to the hierarchically porous structure of NPCs.53 The Ragone plots of activated polypyrrole powder, cPPA, and NPCs are displayed in Figure S12 (Supporting Information). It can also be observed that NPCs possess higher electrochemical performance than the activated polypyrrole powder and cPPA. The good electrochemical performance of NPC as supercapacitor electrode can be ascribed to the hierarchically porous structure, low charge-transfer resistance, and the nitrogen species. First, the hierarchically porous structure is beneficial to the excellent


Page 23 of 34 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


electrolyte transfer capability. The dimensions of hydrated SO42− and H+ in aqueous sulfuric acid solution are 0.38 and 0.28 nm, respectively, which make the ions easy to diffuse through the micropores.54 Second, the low charge-transfer resistance can facilitate the electron transfer. The existence of the mesopores may promote the rate of ion transfer to reduce the inner resistance of NPC.55 Third, the nitrogen species can provide the active site to promote the electrochemical performance. The transformation from pyrrolic nitrogen to quaternary-N and pyridinic nitrogen of NPC during the activation process can introduce some surface functional sites into the porous carbon materials.31,32 The plentiful nitrogen species can provide chemically active sites to improve specific capacity of NPC electrode for supercapacitors.3 Although the capacitance of NPC is lower than those of the samples prepared by chemical activation,47 considering the preparation process, physical activation may be a better way to prepare NPC due to its environmentally friendly characteristic. The obvious disadvantages of the chemical activation treatment are the additional necessary washing procedure and the high corrosion, which is unfavorable for the practical preparation of NPC compared with the physical activation.9,56 Moreover, the capacitance retention and charge–discharge stability of NPC are better than many other materials.45,57,58 Therefore, NPC is not only a suitable material used for the uptake of carbon dioxide, but also a kind of potential materials used for the electrode material as supercapacitor.

CONCLUSIONS



Page 24 of 34

A facile method to prepare the PPA with 3D structure on a large scale is reported, in which P123 plays a role as the dispersant. The PPA shows higher porosity compared with the conventional bulk polypyrrole powder and the existence of the high porosity in PPA provides favorable conditions to the subsequent activation treatment. The NPC prepared through a carbon dioxide activation of PPA possesses a high BET specific surface area (2330 m2 g–1), large pore volume (2.54 cm3 g–1), and nitrogen doping (4.1 wt%). According to these excellent physical and chemical properties, NPC exhibits high carbon dioxide adsorption capacity of 20.5 wt% at 273 K and 1.0 bar. Moreover, these features also provide NPC with decent specific capacitance (156 F g–1 at 0.1 A g–1) and excellent long-term cycling stability (~100 % capacitance retention at 5 A g–1 after 10000 cycles).

ASSOCIATED CONTENT Supporting Information Digital photos of the PPA; SEM and TEM images of cPPA; XPS C1s spectra of PPA, cPPA, and NPC-950-100; TGA and Raman spectra of PPA, cPPA, and NPC-950-100; Typical nitrogen adsorption–desorption isotherm of polypyrrole powder, PPA, and activated polypyrrole powder; Specific capacitance of discharge current density for the activated polypyrrole powder, cPPA, and NPCs; CV curves, Galvanostatic charge– discharge curves, Nyquist plots, and Ragone plots of the activated polypyrrole powder, cPPA, and NPCs; Porous properties of PPA, cPPA, and NPCs samples; Comparison of


Page 25 of 34 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


carbon dioxide uptake (273 K and 1.0 bar) for different porous adsorbents; Comparison of specific capacitance and capacitance retention for different porous carbon electrodes. This information is available free of charge via the Internet at http://pubs.acs.org/.

AUTHOR INFORMATION Corresponding Authors *E-mail: [email protected]. Phone: +86 10 8254 5576. *E-mail: [email protected]. Phone: +86 10 8254 5565. ORCID Bao-Hang Han: 0000-0003-1116-1259 Notes The authors declare no competing financial interest.

ACKNOWLEDGEMENTS The financial support of the National Natural Science Foundation of China (Grants 21574032 and 51602070) and the Ministry of Science and Technology of China (Grant 2013CB934200) is acknowledged.

References [1] Xu, Z. X.; Zhuang, X. D.; Yang, C. Q.; Cao, J.; Yao, Z. Q.; Tang, Y. P.; Jiang, J. Z.; Wu,



Page 26 of 34

D. Q.; Feng, X. L. Nitrogen-Doped Porous Carbon Superstructures Derived from Hierarchical Assembly of Polyimide Nanosheets. Adv. Mater. 2016, 28, 1981–1987. [2] Jia, R. R.; Chen, J. Z.; Zhao, J. H.; Zheng, J. F.; Song, C.; Li, L.; Zhu, Z. P. Synthesis of Highly Nitrogen-Doped Hollow Carbon Nanoparticles and Their Excellent Electrocatalytic Properties in Dye-Sensitized Solar Cells. J. Mater. Chem. 2010, 20, 10829–10834. [3] Chen, L.-F.; Zhang, X.-D.; Liang, H.-W.; Kong, M.-G.; Guan, Q.-F.; Chen, P.; Wu, Z.-Y.; Yu, S.-H. Synthesis of Nitrogen-Doped Porous Carbon Nanofibers as an Efficient Electrode Material for Supercapacitors. ACS Nano 2012, 6, 7092–7102. [4] Jalilov, A. S.; Ruan, G. D.; Hwang, C. C.; Schipper, D. E.; Tour, J. J.; Li, Y. L.; Fei, H. L.; Samuel, E. L. G.; Tour, J. M. ACS Appl. Mater. Interfaces 2015, 7, 1376–1382. [5] Yang, M. L.; Guo, L. P.; Hu, G. S.; Hu, X.; Xu, L. Q.; Chen, J.; Dai, W.; Fan, M. H. Highly Cost-Effective Nitrogen-Doped Porous Coconut Shell-Based CO2 Sorbent Synthesized by Combining Ammoxidation with KOH Activation. Environ. Sci. Technol. 2015, 49, 7063–7070. [6] Kubota, M.; Hata, A.; Matsuda, H. Preparation of Activated Carbon from Phenolic Resin by KOH Chemical Activation under Microwave Heating. Carbon 2009, 47, 2805– 2811. [7] Sevilla, M.; Valle-Vigón, P.; Fuertes, A. B. N-Doped Polypyrrole-Based Porous Carbons for CO2 Capture. Adv. Funct. Mater. 2011, 21, 2781–2787. [8] Wickramaratne, N. P.; Jaroniec, M. Activated Carbon Spheres for CO2 Adsorption. ACS Appl. Mater. Interfaces 2013, 5, 1849–1855. [9] Lee, H.-M.; Kang, H.-R.; An, K.-H.; Kim, H.-G.; Kim, B.-J. Comparative Studies of

26


Page 27 of 34 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


Porous Carbon Nanofibers by Various Activation Methods. Carbon Lett. 2013, 14, 180– 185. [10] Lee, S.-Y.; Park S.-J. Effects of CO2 Activation on Electrochemical Performance of Microporous Carbons Derived from Poly(Vinylidene Fluoride). J. Solid State Chem. 2013, 207, 158–162. [11] Górka, J.; Jaroniec, M. Hierarchically Porous Phenolic Resin-Based Carbons Obtained by Block Copolymer-Colloidal Silica Templating and Post-Synthesis Activation with Carbon Dioxide and Water Vapor. Carbon 2011, 49, 154–160. [12] Sui, Z.-Y.; Meng, Q.-H.; Li, J.-T.; Zhu, J.-H.; Cui, Y.; Han, B.-H. High Surface Area Porous Carbons Produced by Steam Activation of Graphene Aerogels. J. Mater. Chem. A 2014, 2, 9891–9898. [13] Kistler, S. S. Coherent Expanded Aerogels and Jellies. Nature 1931, 127, 741–741. [14] Zou, J. H.; Liu, J. H.; Karakoti, A. S.; Kumar, A.; Joung, D.; Li, Q.; Khondaker, S. I.; Seal, S.; Zhai, L. Ultralight Multiwalled Carbon Nanotube Aerogel. ACS Nano 2010, 4, 7293–7302. [15] Hu, H.; Zhao, Z. B.; Wan, W. B.; Gogotsi, Y.; Qiu, J. S. Ultralight and Highly Compressible Graphene Aerogels. Adv. Mater. 2013, 25, 2219–2223. [ 16 ] Sui, Z.-Y.; Meng, Y.-N.; Xiao, P.-W.; Zhao, Z.-Q.; Wei, Z.-X.; Han, B.-H. Nitrogen-Doped Graphene Aerogels as Efficient Supercapacitor Electrodes and Gas Adsorbents. ACS Appl. Mater. Interfaces 2015, 7, 1431–1438. [17] Shi, Y.; Pan, L. J.; Liu, B. R.; Wang, Y. Q.; Cui, Y.; Bao, Z. N.; Yu, G. H. Nanostructured Conductive Polypyrrole Hydrogels as High-Performance, Flexible

27



Page 28 of 34

Supercapacitor Electrodes. J. Mater. Chem. A 2014, 2, 6086–6091. [ 18 ] Hüsing, N.; Schubert, U. Aerogels-Airy Materials: Chemistry, Structure, and Properties. Angew. Chem. Int. Ed. 1998, 37, 22–45. [19] Kabbour, H.; Baumann, T. F.; Satcher, J. H.; Saulnier, A.; Ahn, C. C. Toward New Candidates for Hydrogen Storage: High-Surface-Area Carbon Aerogels. Chem. Mater. 2006, 8, 6085–6087. [20] Rolisona, D. R.; Dunnb, B. Electrically Conductive Oxide Aerogels: New Materials in Electrochemistry. J. Mater. Chem. 2001, 11, 963–980. [ 21 ] Moreno-Castilla, C.; Maldonado-Hόdar, F. J. Carbon Aerogels for Catalysis Applications: An Overview. Carbon 2005, 43, 455–465. [22] Hur, J.; Im, K.; Kim, S. W.; Kim, J.; Chung, D. Y.; Kim, T. H.; Jo, K. H.; Hahn, J. H.; Bao, Z. N.; Hwang, S.; Park, N. Polypyrrole/Agarose-Based Electronically Conductive and Reversibly Restorable Hydrogel. ACS Nano 2014, 8, 10066–10076. [23] Huang, H.; Wu, J.; Lin, X.; Li, L.; Shang, S. M.; Yuen, M. C.; Yan, G. P. Self-Assembly of Polypyrrole/Chitosan Composite Hydrogels. Carbohydr. Polym. 2013, 95, 72–76. [24] Smirnov, M. A.; Bobrova, N. V.; Dmitriev, I. Y.; Bukolšek, V.; Elyashevich, G. K. Electroactive Hydrogels Based on Poly (Acrylic Acid) and Polypyrrole. Polym. Sci. Ser. A 2011, 53, 67–74. [25] Yan, Z.; Gu, Y.; Wei, W.; Jiang, Z.; Xie, J.; Shen, P. K. Tungsten Carbide Synthesized by Polystyrene Sphere Template Method Promoting Pd Electrocatalyst for Alcohol Oxidation in Alkaline Media. Full Cells 2015, 15, 256−261.

28


Page 29 of 34 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


[26] Lund, K.; Garcia-Bennett, A. E.; Terasaki, O. On the Use of Polymeric Dispersant P123 in the Synthesis of Bicontinuous Cubic Mesoporous AMS-6. J. Mater. Chem. 2007, 17, 3622−3629. [27] Tennison, S.R. Phenolic-Resin-Derived Activated Carbons. Appl. Catal. A 1998, 173, 289–311. [28] Pels, J. R.; Kapteijn, F.; Moulijn, J. A.; Zhu, Q.; Thomas, K. M. Evolution of Nitrogen Functionalities in Carbonaceous Materials During Pyrolysis. Carbon 1995, 33, 1641−1653. [ 29 ] Weidenthaler, C.; Lu, A. H.; Schmidt, W.; Schüth, F. X-ray Photoelectron Spectroscopic Studies of PAN-Based Ordered Mesoporous Carbons (OMC). Micropor. Mesopor. Mater. 2006, 88, 238−243. [30] Kelemen, S. R.; Gorbaty, M. L.; Kwiatek, P. J. Quantification of Nitrogen Forms in Argonne Premium Coals. Energy Fuels 1994, 8, 896–906. [31] Su, F.; Poh, C. K.; Chen, J. S.; Xu, G.; Wang, D.; Li, Q.; Lin, J.; Lou, X. W. Nitrogen-Containing Microporous Carbon Nanospheres with Improved Capacitive Properties. Energy Environ. Sci. 2011, 4, 717–724. [ 32 ] Shrestha, S.; Mustain, W. E. Properties of Nitrogen-Functionalized Ordered Mesoporous Carbon Prepared Using Polypyrrole Precursor. J. Electrochem. Soc. 2010, 157, B1665–B1672. [33] Li, W.; Chen, D.; Li, Z.; Shi, Y.; Wan, Y.; Huang, J.; Yang, J.; Zhao, D.; Jiang, Z. Nitrogen Enriched Mesoporous Carbon Spheres Obtained by a Facile Method and Its Application for Electrochemical Capacitor. Electrochem. Commun. 2007, 9, 569–573. [34] Yang, Q.-S.; Sui, Z.-Y.; Liu, Y.-W.; Han, B.-H. Porous Nitrogen-Doped Carbon

29



Page 30 of 34

Nanoribbons for High-Performance Gas Adsorbents and Lithium Ion Batteries. Ind. Eng. Chem. Res. 2016, 55, 6384–6390. [35] Pina, C. D.; Falletta, E.; Faro, M. L.; Pasta, M.; Rossi, M. Gold-Catalysed Synthesis of Polypyrrole. Gold Bull. 2009, 42, 27−33. [36] Nabid, M. R.; Entezami, A. A. A Novel Method for Synthesis of Water-Soluble Polypyrrole with Horseradish Peroxidase Enzyme. J. Appl. Polym. Sci. 2004, 94, 254−258. [37] Zhang, X. T.; Zhang, J.; Song, W. H.; Liu, Z. F. Controllable Synthesis of Conducting Polypyrrole Nanostructures. J. Phys. Chem. B 2006, 110, 1158−1165. [ 38 ] Li, X.-G.; Wei, F.; Huang, M.-R.; Xie, Y.-B. Facile Synthesis and Intrinsic Conductivity of Novel Pyrrole Copolymer Nanoparticles with Inherent Self-Stability. J. Phys. Chem. B 2007, 111, 5829−5836. [39] Chen, H. C.; Wei, Y. J.; Wang, J. T.; Qiao, W. M.; Ling, L. C.; Long, D. H. Controllable Nitrogen Doping of High-Surface-Area Microporous Carbons Synthesized from an Organic-Inorganic Sol-Gel Approach for Li-S Cathodes. ACS Appl. Mater. Interfaces 2015, 7, 21188−21197. [40] Rasines, G.; Lavela, P.; Macías, C.; Zafra, M. C.; Tirado, J. L.; Parra, J. B.; Ania, C. O. N-Doped Monolithic Carbon Aerogel Electrodes with Optimized Features for the Electrosorption of Ions. Carbon 2015, 83, 262−274. [41] Chen, Q.; Luo, M.; Hammershøj, P.; Zhou, D.; Han, Y.; Laursen, B. W.; Yan, C.-G.; Han, B.-H. Microporous Polycarbazole with High Specific Surface Area for Gas Storage and Separation. J. Am. Chem. Soc. 2012, 134, 6084–6087. [42] Sui, Z.-Y.; Cui, Y.; Zhu, J.-H.; Han, B.-H. Preparation of Three-Dimensional Graphene

30


Page 31 of 34 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


Oxide-Polyethylenimine Porous Materials as Dye and Gas Adsorbents. ACS Appl. Mater. Interfaces 2013, 5, 9172−9179. [43] Ben, T.; Pei, C. Y.; Zhang, D. L.; Xu, J.; Deng, F.; Jing, X. F.; Qiu, S. L. Gas Storage in Porous Aromatic Frameworks (PAFs). Energy Environ Sci 2011, 4, 3991−3999. [44] Yu, J.; Guo, M. Y.; Muhammad, F.; Wang, A. F.; Zhang, F.; Li, Q.; Zhu, G. S. One-Pot Synthesis

of

Highly

Ordered

Nitrogen-Containing

Mesoporous

Carbon

with

Resorcinol-Urea-Formaldehyde Resin for CO2 Capture. Carbon 2014, 69, 502–514. [45] Sevilla, M.; Parra, J. B.; Fuertes, A. B. Assessment of the Role of Micropore Size and N-Doping in CO2 Capture by Porous Carbons. ACS Appl. Mater. Interfaces 2013, 5, 6360−6368. [46] Lee, J. H.; Lee, H. J.; Lim, S. Y.; Kim, B. G.; Choi, J. W. Combined CO2-philicity and Ordered Mesoporosity for Highly Selective CO2 Capture at High Temperatures. J Am. Chem. Soc. 2015, 137, 7210−7216. [47] Ferrero, G. A.; Fuertes, A. B.; Sevilla, M. N-Doped Porous Carbon Capsules with Tunable Porosity for High-Performance Supercapacitors. J. Mater. Chem. A 2015, 3, 2914– 2923. [48] Qie, L.; Chen, W. M.; Xu, H. H.; Xiong, X. Q.; Jiang, Y.; Zou, F.; Hu, X. L.; Xin, Y.; Zhang, Z. L.; Huang, Y. H. Synthesis of Functionalized 3D Hierarchical Porous Carbon for High-Performance Supercapacitors. Energy Environ. Sci. 2013, 6, 2497–2504. [49] Zhang, J. S.; Lee, J. W. Supercapacitor Electrodes Derived from Carbon Dioxide. ACS Sust. Chem. Eng. 2014, 2, 735–740. [50] Lee, H. M.; Kim, H. G.; An, K. H.; Kim, B. J. Effects of Pore Structures on

31



Page 32 of 34

Electrochemical Behaviors of Polyacrylonitrile-Based Activated Carbon Nanofibers by Carbon Dioxide Activation. Carbon Lett. 2014, 15, 71–76. [51] Wu, C.; Xu, J.; Ding, J. N.; Yuan, N. Y.; Yan, P. T.; Zhang, R. J.; Liu, H. H. High-Performance Supercapacitor Based on the NaOH Activated D-Glucose Derived Carbon. Nano 2016, 11, 1650075 (1–9). [52] Yang, L.; Cheng, S.; Ding, Y.; Zhu, X. B.; Wang, Z. L.; Liu, M. L. Hierarchical Network Architectures of Carbon Fiber Paper Supported Cobalt Oxide Nanonet for High-Capacity Pseudocapacitors. Nano Lett. 2012, 12, 321–325. [53] Li, J.; Liu, K.; Gao, X.; Yao, B.; Huo, K. F.; Cheng, Y. L.; Cheng, X. F.; Chen, D. C.; Wang, B.; Sun, W. M.; Ding, D.; Liu, M. L.; Huang, L. Oxygen- and Nitrogen-Enriched 3D Porous Carbon for Supercapacitors of High Volumetric Capacity. ACS Appl. Mater. Interfaces 2015, 7, 24622–14628. [54] Nightingale, E. R. Phenomenological Theory of Ion Solvation. Effective Radii of Hydrated Ions. J. Phys. Chem. 1959, 63, 1381–1387. [55] Kim, W.; Kang, M. Y.; Joo, J. B.; Kim, N. D.; Song, I. K.; Kim, P.; Yoon, J. R.; Yi, J. Preparation of Ordered Mesoporous Carbon Nanopipes with Controlled Nitrogen Species for Application in Electrical Double-layer Capacitors. J. Power Sources 2010, 195, 2125– 2129. [56] Lozano-Castelló, D.; Calo, J. M.; Cazorla-Amorós, D.; Linares-Solano, A. Carbon Activation with KOH as Explored by Temperature Programmed Techniques, and the Effects of Hydrogen. Carbon 2007, 45, 2529–2536. [57] Izadi-Najafabadi, A.; Yasuda, S.; Kobashi, K.; Yamada, T.; Futaba, D. N.; Hatori, H.;

32


Page 33 of 34 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


Yumura, M.; Iijima, S.; Hata, K. Extracting the Full Potential of Single-Walled Carbon Nanotubes as Durable Supercapacitor Electrodes Operable at 4 V with High Power and Energy Density. Adv. Mater. 2010, 22, E235–E241. [58] Sevilla, M.; Fuertes, A. B. Direct Synthesis of Highly Porous Interconnected Carbon Nanosheets and Their Application as High-Performance Supercapacitors. ACS Nano 2014, 8, 5069–5078.

33



Page 34 of 34


Nitrogen-Doped Porous Carbons Derived from Polypyrrole-Based

Recommend Documents